The complete
episome of EqPV-H comprises 5,308 nt and is predicted to code 2 large open reading frames whose proteins are related to the NS proteins and the structural proteins (VPs) of known animal parvoviruses (Figures 1, 2).
Using PCR (2 sets of specific primers), we did not detect the vector DNA either as
episomes or anywhere in the iPSC genome analyzed, after about 10 passages.
Consistent with this function, LANA is often detected as punctate nuclear speckles depicting discrete foci of LANA-mediated tethering of viral
episomes to host DNA [49].
The EBV genome is maintained in B cells, either as a multicopy circular
episome in the host cell or by integrating the viral DNA into the host genome.
The key step protected by this patent relates to a process known as 'episomal expression' whereby genes of interest remain as free DNA in the cell (an '
episome') rather than being integrated into the chromosome, and this results in more efficient expression of the genes and molecules under assay.
EBV can enter into a latent phase of replication, during which the genome persists as a circular
episome in the cell nucleus, with only minimal activity of select viral genes.
Instead, its DNA forms an independent loop, called an
episome, that resides in the nucleus.
Not integrated into our genome, It will roam, that
episome. The DNA of herpes.
The HPV16 integration status was confirmed using the rate of E2 to E6 copy number, and the results indicated that 2.6% (2/76) with E2/E6 ratios >1 in the HPV16 positive samples uniquely belonged to the
episome status, 85.6% (65/76) with 0<E2/E6 ratios<1 belonged to the mix status (including
episome and integration), and 11.8% (9/76) with E2/E6 ratios=0 exclusively belonged to the integrated status.
The circular
episome, located in the cellular envelope protein, is responsible for viral attachment to the host cell.
Latency is characterized by maintenance of the viral genome as a nonintegrated
episome and expression of a limited number of viral genes and microRNAs.
The viral genome is maintained in these cells as a stable
episome at low copy number, and it is these infected cells that form the reservoir for the development of a productive wart (9).
